Acyclic amine epoxide process

ABSTRACT

Acyclic amines are used to transform 9α-substituted-11β-hydroxy 21-acyloxy steroids to the corresponding 9β,11β-epoxy 21-acyloxy steroids without removal of the C 17  or C 21  ester. The acyclic amines are cheaper and easier to prepare than previously disclosed dehydrohalogenating agents which do not produce cleavage of the C 21  ester.

CROSS REFERENCE TO RELATED APPLICATION

This patent application is a continuation-in-part patent application of co-pending patent application Ser. No. 431,548, filed Sept. 30, 1982 and now abandoned.

BACKGROUND OF THE INVENTION

The transformations of Δ⁹ (¹¹)-steroids to the corresponding bromohydrins (9α-bromo-11β-hydroxy steroid) then to the corresponding 9β,11β-epoxy steroids and finally by reaction with hydrogen fluoride to the desired 9α-fluoro-11β-hydroxy steroids are well known. Various agents have been used for the epoxidation reaction including strong bases such as methoxide, t-butoxide or sodium hydroxide in methanol (U.S. Pat. Nos. 2,838,493 and 3,725,392), potassium acetate in acetone (U.S. Pat. No. 3,980,778), and J. Am. Chem. Soc. 77, 4438 (1955), potassium fluoride in particular solvents (U.S. Pat. No. 3,255,185) and cyclic amidine bases such as DBU (U.S. Pat. No. 4,207,235).

The closure of the 9α-bromo-11β-hydroxy bromohydrin to the corresponding 9β,11β-epoxide is a dehydrohalogenation reaction.

H. Oediger, et al. in Synthesis 591 (1972) compare the elimination of hydrogen chloride by various organic bases. Table 1 on p. 592 shows that cyclic and acyclic amines and acyclic amidines do not work in the dehydrohalogenation reaction nearly as well as DBN. Hence, it would be expected that acyclic amidines would not transform the 9α-bromo-11β-hydroxy bromohydrin to the corresponding 9β,11β-epoxide nearly as well as does DBN or DBU.

D. H. R. Barton in J.C.S. Chem. Comm. 1136 (1981) reports the preparation of a number of guanidines which are strong organic bases. Barton did not report that these bases would be useful in a dehydrohalogenation reaction such as the transformation of a bromohydrin to the corresponding epoxide.

The present invention involves acyclic guanidines and amidines which surprisingly and unexpectedly efficiently effect the transformation of 9α-substituted-11β-hydroxy steroids (I) to the corresponding 9β,11β-epoxides (II). The guanidines (III) and amidines (IV) are less expensive and easier to make than other known dehydrohalogenating agents such as DBU and DBN and do not cleave 21-acyloxy groups as to most other bases.

BRIEF DESCRIPTION OF THE INVENTION

Disclosed is a process for the preparation of an epoxide of formula (II) which comprises contacting a 9α-substituted-11β-hydroxy steroid of formula (I) with an acyclic amine selected from the group consisting of guanidines of formula (III) and amidines of the formula (IV) and isolating the epoxide (II).

DETAILED DESCRIPTION OF THE INVENTION

The 9α-substituted-11β-hydroxy steroid (I) starting materials are well known to those skilled in the art or can be readily prepared by known methods from compounds well known to those skilled in the art.

The process of the present invention for the transformation of the 9α-substituted-11β-hydroxy steroid (I) to the epoxide (II) is operable with a wide widely of steroid A-rings. Preferred are the Δ⁴ -3-keto (A), Δ¹,4 -3-keto (B) and 3β-hydroxy-Δ⁵ (C) steroid A rings, see Chart B.

The fluorine atom or methyl group at the C-6 position does not interfere in any way in the process of the present invention. The leaving group, R₉, is a chlorine, bromine or iodine atom or a hydroxyl group as the tosylate, mesylate or triflate ester. It is preferred that R₉ be a bromine atom. R₁₆ is a hydrogen atom, hydroxyl or methyl group. When R₁₆ is a hydroxyl group and there is a hydroxyl group at C₁₇, the hydroxyl groups can be in the form of an acetonide. R₁₇ is a hydrogen atom or --COR₁₇ α wherein R₁₇ α is alkyl of one thru 6 carbon atoms or phenyl. When R₁₇ is a hydrogen atom and R₁₆ is a hydroxyl group, the hydroxyl groups can be in the form of an acetonide. R₂₁ is alkyl of one thru 6 carbon atoms, phenyl or phenyl substituted with p-nitro or m-methoxy groups. The process of the present invention is applicable equally to Δ⁴ -3-keto steroids and Δ.sup. 1,4 -3-keto steroids. The preferred steroid D ring is that set forth in Chart C as formula (D).

The acyclic amidines (IV) are known to those skilled in the art or can be readily prepared from known compounds by methods well known to those skilled in the art, see, for example, J. Am. Chem. Soc. 102, 7125 (1980) and M. Bredereck et al., Chem. Ber, 96, 1350 (1963). R_(a) is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms or phenyl substituted with one thru 3 --R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a secondary amine selected from the group consisting of piperidine, pyrrolidine or morpholine. It is preferred that R_(a) be t-butyl. R'₃ and R'₄ can be the same or different and are alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms or phenyl substituted with one thru 3 --R, --OR₅₀ or --N(R₅₀)₂ with the proviso that R'₃ and R'₄ combined cannot have more than 14 carbon atoms; R'₃ and R'₄ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine. It is preferred that both R'₃ and R'₄ be methyl.

The guanidines of formula (III) are well known to those skilled in the art or can be readily prepared from known compounds by methods well known by those skilled in the art. See Barton, supra. R_(g) is identical with R_(a) except that it also includes the hydrogen atom, phenyl and p-tolyl group. It is preferred that R_(g) be a hydrogen atom. R₁, R₂, R₃ and R₄ are the same or different and are alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with zero thru 3, --R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a secondary amine selected from the group consisting of piperidine, pyrrolidine or morpholine with the proviso that R₁ -R₂ and R₃ -R₄ combined cannot have more than 14 carbon atoms; R₁ -R₂ and R₃ - R₄ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine. It is preferred that R₁, R₂, R₃ and R₄ a 11 be methyl groups or hydrogen atoms.

Tables 1 and 2 disclose that while the guanidines (III) and amidines (IV) are operable in the process of the present invention some are preferred.

The 9α-substituted-11β-hydroxy steroid (I) is contacted with either an acyclic guanidine (III) or an acyclic amidine (IV) in an aprotic polar organic solvent selected from the group consisting of methylene chloride, acetone, ethyl acetate, DMSO, DMF, THF, dioxane, acetonitrile, toluene and chloroform. It is preferred that the aprotic polar solvent be DMF.

One to two equivalents of the guanidine (III) or amidine (IV) per equivalent of steroid are used. It is preferred that approximately 1.1 equivalents of the guanidine (III) or amidine (IV) per equivalent of steroid be used.

The reaction is preferably performed under a nitrogen atmosphere although this is not necessary.

The reaction is performed in the temperature range of 0°-100° depending on the nature of the guanidine (III) or amidine (IV) used. When the acyclic amine is the guanidine (III) the reaction is generally performed in the temperature range of 0°-40° with 25°-35° being preferred. When the acyclic amine is the amidine (IV) the reaction is generally performed in the temperature range of 70°-100° with 80°-90° being preferred. The reaction can be performed in a sealed container with heat which shortens the reaction time. Generally the reaction is performed at the reflux temperature of the organic diluent being used.

The reaction is monitored by TLC which generally indicates the reaction is complete in approximately one hr with guanidines (III) and approximately 4-5 hr with the amidines (IV).

When the reaction is complete as measured by TLC the reaction mixture is diluted with water containing an acid such as hydrochloric, acetic, sulfuric, phosphoric, or p-TSA. The desired epoxide (II) is extracted from the reaction medium by methods well known to those skilled in the art or isolated by water knock-out and filtration.

The epoxides (II) are useful for conversion to the corresponding 9α-fluoro-11β-hydroxy steroids by reaction of the epoxide with hydrogen fluoride as is well known to those skilled in the art, see Fried, et al., J. Am. Chem. Soc. 76,1455 (1954); Hirschman, et al., J. Am. Chem. Soc. 4957 (1956); U.S. Pat. Nos. 2,894,007, 3,049,556, 3,086,032, 3,007,923, 3,211,758 and 3,980,778.

Therefore the process of the present invention permits transformation of the 9α-substituted-11β-hydroxy 21-esters to the corresponding 9β,11β-epoxide 21-esters (II) without cleavage of the 21 ester group utilizing bases which are less expensive and more easily prepared than DBU and DBN.

DEFINITIONS

The definitions and explanations below are for the terms as used throughout the entire patent application including both the specification and the claims.

All temperatures are in degrees Centigrade.

TLC refers to thin-layer chromatography.

THF refers to tetrahydrofuran.

DMSO refers to dimethylsulfoxide.

DMF refers to dimethylformamide.

p-TSA refers to p-toluenesulfonic acid, monohydrate.

When solvent pairs are used, the ratio of solvents used are volume/volume (v/v).

DBU refers to 1,8-diazabicyclo[5.4.0]undec-7-ene.

DBN refers to 1,5-diazabicyclo[4.3.0]non-5-ene.

When the term of " thru carbon atoms" is used, it includes isomers thereof.

R is alkyl of 1 thru 3 carbon atoms.

R_(a) is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with one thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine.

R_(g) is R_(a) and a hydrogen atom, or phenyl.

R₁ is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with zero thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine with the proviso that R₁ and R₂ combined cannot have more than 14 carbon atoms; R₁ and R₂ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine.

R₂ is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with zero thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine with the proviso that R₁ and R₂ combined cannot have more than 14 carbon atoms; R₁ and R₂ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine.

R₃ is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with zero thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine with the proviso that R₃ and R₄ combined cannot have more than 14 carbon atoms; R₃ and R₄ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine.

R₃ ' is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with one thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a secondary amine selected from the group consisting of piperidine, pyrrolidine or morpholine, with the proviso that R₃ ' and R₄ ' combined cannot have more than 14 carbon atoms; R₃ ' and R₄ ' combined cannot have more than 14 carbon atoms; R₃ ' and R₄ ' can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine.

R₄ is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with zero thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine with the proviso that R₃ and R₄ combined cannot have more than 14 carbon atoms; R₃ and R₄ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine.

R₄ ' is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with one thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a secondary amine selected from the group consisting of piperidine, pyrrolidine or morpholine, with the proviso that R₃ ' and R₄ ' combined cannot have more than 14 carbon atoms; R₃ ' and R₄ ' can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine.

R₆ is a hydrogen or fluorine atom or methyl group.

R₉ is a chlorine, bromine or iodine atom or hydroxyl group as the tosylate, mesylate, or triflate ester.

R₁₆ is a hydrogen atom, hydroxyl, acyloxy where the acyl group contains 2 thru 6 carbon atoms, or methyl group with the proviso that when R₁₆ is a hydroxyl group and when R₁₇ is a hydrogen atom the hydroxyl groups at C₁₆ and C₁₇ can be in the form of an acetonide.

R₁₇ is a hydrogen atom or a --COR₁₇ α group with the proviso that when R₁₇ is a hydrogen atom and R₁₆ is a hydroxyl group the hydroxyl groups at C₁₆ and C₁₇ can be in the form of an acetonide.

R₁₇ α is an alkyl of one thru 6 carbon atoms or phenyl.

R₂₁ is alkyl of one thru 6 carbon atoms or phenyl, or phenyl substituted with p-nitro or m-methoxy groups.

R₅₀ is a hydrogen atom or alkyl of 1 thru 3 carbon atoms.

˜ indicates the attached atom or group can be in the alpha or beta configuration.

is a single or double bond.

EXAMPLES

Without further elaboration, it is believed that one skilled in the art can, using the preceding description, practice the present invention to its fullest extent. The following detailed examples describe how to prepare the various compounds and/or perform the various processes of the invention and are to be construed as merely illustrative, and not limitations of the preceding disclosure in any way whatsoever. Those skilled in the art will promptly recognize appropriate variations from the procedures both as to reactants and as to reaction conditions and techniques.

EXAMPLE 1 9β,11β-Epoxy-17α,21-dihydroxypregna-1,4-diene-3,20-dione 21-acetate (II)

9α-Bromo-11β,17α,21-trihydroxypregna-1,4-diene-3,20-dione 21-acetate (I, JACS 77, 4438 (1955), 2.406 g) in DMF (12 ml) is stirred under nitrogen in a 12° water bath. Tetramethylguanidine (0.656 ml) is added to the mixture which is stirred overnight. Water (20 ml) containing hydrochloric acid (1 N, 1.0 ml) is added with stirring. The mixture is cooled in an ice water bath during the water/hydrochloric acid addition. Water (13 ml) is slowly added to the mixture at -10° with stirring. The mixture is stirred at 6° for 20 min. The solid is filtered, washed three times with water and dried under reduced pressure at 50°-60° for 31/2 hr to give the title compound.

EXAMPLE 2 9β,11β-Epoxy-17α,21-dihydroxypregn-4-ene-3,20-dione 21-acetate (II)

9α-Bromo-11β,17α,21-trihydroxypregn-4-ene-3,20-dione 21-acetate (I, JACS 77, 4438 (1955), 2.00 g) is dissolved in DMF (5 ml). Tetramethylguanidine (0.475 g) is added and the mixture is stirred at 20°-25°. When TLC indicated the reaction is done, water containing 10% hydrochloric acid is added, the mixture stirred, the solids are collected by filtration, washed, and dried under reduced pressure to give the title compound.

EXAMPLE 3 9β,11β-Epoxy-17α,21-dihydroxy-16β-methylpregna-1,4-diene-3,20-dione 21-benzoate (II)

9α-Bromo-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione 21-benzoate (I, U.S. Pat. No. 3,164,618, Example 30, 2.0 g) is slurried in methylene chloride (10 ml). t-Butyldimethylamidine (0.86 g) is added and the mixture heated to reflux. After 6 hr TLC indicates the reaction is about 90% complete. The organic solvent is replaced with ethyl acetate, the mixture filtered and the solid dried under reduced pressure to give the title compound.

EXAMPLE 4 9β,11β-Epoxy-17α,21-dihydroxy-16α-methylpregna-1,4-diene-3,20-dione 21-acetate (II)

9α-Bromo-11β,17α,21-trihydroxy-16α-methylpregna-1,4,-diene-3,20-dione 21-acetate (I, U.S. Pat. No. 3,164,618, Example 40(c), 1.00 g) is is slurried in methylene chloride (5 ml). t-Butyldimethylamidine (0.43 ml) is added and the mixture heated to reflux overnight. The methylene chloride is replaced with ethyl acetate, the mixture filtered, and the solids dried under reduced pressure to give the title compound.

EXAMPLE 5 Comparison of Expoxidation Reaction using DBU and Tetramethylguanidine

A. DBU

9α-Bromo-11β,17α,21-trihydroxypregn-4-ene-3,20-dione 21-acetate (I, 4.0 g) and DMF (20 ml) were mixed at 5°. DBU (1.49 ml, 9.94 mmole) was added. After 15 min, water (50 ml) containing 10% aqueous hydrochloric acid was added, the mixture was stirred and filtered, the solids were washed with water and dried to give 9β,11β-epoxy-17α,21-dihydroxy-pregna-4-ene-3,20-dione 21-acetate (II) in 93.2% yield.

B. Tetramethylguanidine

9α-Bromo-11β,17α,21-trihydroxypregn-4-ene-3,20-dione 21-acetate (I, 4.0 g) and DMF (20 ml) were mixed at 5°. Tetramethylguanidine (1.24 ml, 9.94 mmole) was added. After 15 min, water (50 ml) containing 10% aqueous hydrochloric acid was added. The mixture was stirred and filtered. The solids were washed with water and dried to give 9β,11β-epoxy-17α,21-dihydroxypregn-4-ene-3,20-dione 21-acetate (II) in 92.3% chemical yield.

EXAMPLE 6 6α-Fluoro-9β,11β-epoxy-16α,17α,21-trihydroxypregna-1,4-diene-3,20-dione 16,17-acetonide-21-acetate (II)

9α-Bromo-6α-fluoro-11β,16α,17α,21-tetrahydroxypregna-1,4-diene-3,20-dione 16,17-acetonide-21-acetate (I, J. Am. Chem. Soc. 77, 4438 (1957), 2.64 g) is dissolved in DMF (15 ml) at 20°-25°. Tetramethylguanidine (III, 0.62 g) is added, and the mixture stirred for 15 min. Water (30 ml) and a little hydrochloric acid (10%) are added. The mixture is cooled and filtered. The solids are washed with cold water and dried in an oven overnight to give the title compound.

EXAMPLE 7 9β,11β-Epoxy-16α,17α,21-trihydroxypregn-4-ene-3,20-dione 16,21-diacetate (II)

Following the general procedure of Example 1 and making non-critical variations, but starting with 9α-bromo-11β,16α,17α,21-tetrahydroxypregn-4-ene-3,20-dione 16,21-diacetate (I, J. Am.Chem. Soc. 81, 1689 (1959)), the title compound is obtained.

EXAMPLE 8 9β,11β-Epoxy-16α,17α,21-trihydroxypregna-1,4-diene-3,20-dione 16,21-diacetate (II)

Following the general procedure of Example 1 and making non-critical variations, but starting with 9α-bromo-11β,16α,17α,21-tetrahydroxypregna-1,4-diene-3,20-dione 16,21-diacetate (I, J. Am. Chem. Soc. 81, 1686 (1959)), the title compound is obtained.

EXAMPLE 9 9β,11β-Epoxy-17α,21-dihydroxypregn-4-ene-3,20-dione 21-acetate (II)

Following the general procedure of Example 5B and making non-critical variations but using guanidine in place of tetramethylguanidine, the title compound is obtained.

EXAMPLES 10-20

Following the procedure of Example 1 and making non-critical variations but starting with the 9α-substituted-11β-hydroxy steroid (I) of Column A, the epoxide (II) of Column B is obtained.

    ______________________________________                                         Ex-                                                                            am-                                                                            ple  Column A          Column B                                                ______________________________________                                         10   9α-Bromo-11β,16α,17α,21-                                                  9β,11β-Epoxy-16α,17α,21-               tetrahydroxypregn-4-en-                                                                          trihydroxypregn-4-en-                                        3,20-dione 21-acetate                                                                            3,20-dione 21-acetate                                   11   6α-Fluoro-9α-bromo-11β,                                                         9β,11β-Epoxy-6α-fluoro-                      16α,17α,21-tetrahydroxy-                                                             16α,17α,21-trihydroxy-                           pregn-4-en-3,20-dione                                                                            pregn-4-en-3,20-dione                                        21-acetate        21-acetate                                              12   9α-Bromo-11β,16α,17α,21-                                                  9β,11β-Epoxy-16α,17α,21-               tetrahydroxypregna-1,4-                                                                          trihydroxypregna-1,4-                                        diene-3,20-dione 21-acetate                                                                      diene-3,20-dione 21-acetate                             13   6α-Fluoro-9α-bromo-11β-                                                         9β,11β-Epoxy-6α-fluoro-                      16α,17α,21-tetrahydroxy-                                                             16α,17α,21-trihydroxy-                           pregna-1,4-diene-3,20-                                                                           pregna-1,4-diene-3,20-                                       dione 21-acetate  dione 21-acetate                                        14   9α-Bromo-11β,17α,21-tri-                                                        9β,11β-Epoxy-17α,21-di-                      hydroxy-16β-methylpregna-                                                                   hydroxy-16β-methylpregna-                               1,4-diene-3,20-dione                                                                             1,4-diene-3,20-dione                                         17,21-diacetate   17,21-diacetate                                         15   9α-Bromo-11β,17α,21-tri-                                                        9β,11β-Epoxy-17α,21-di-                      hydroxy-16β-methylpregna-                                                                   hydroxy-16β-methylpregna-                               1,4-diene-3,20-dione                                                                             1,4-diene-3,20-dione                                         17-benzoate       17-benzoate                                             16   9α-Bromo-11β,17α,21-tri-                                                        9β,11β-Epoxy-17α,21-di-                      hydroxy-16β-methylpregna-                                                                   hydroxy-16β-methylpregna-                               1,4-diene-3,20-dione                                                                             1,4-diene-3,20-dione                                         21-pivalate       21-pivalate                                             17   9α-Bromo-11β,17α,21-tri-                                                        9β,11β-Epoxy-17α,21-di-                      hydroxy-16β-methylpregna                                                                    hydroxy-16β-methylpregna-                               1,4-diene-3,20-dione                                                                             1,4-diene-3,20-dione                                         21-valerate       21-valerate                                             18   9α-Bromo-11β,17α,21-tri-                                                        9β,11β-Epoxy-17α,21-di-                      hydroxy-16β-methylpregna-                                                                   hydroxy-16β-methylpregna-                               1,4-diene-3,20-dione                                                                             1,4-diene-3,20-dione                                         21-propionate     21-propionate                                           19   9α-Bromo-11β,17α,21-tri-                                                        9β,11β-Epoxy-17α,21-di-                      hydroxy-16β-methylpregna-                                                                   hydroxy-16β-methylpregna-                               1,4-diene-3,20-dione                                                                             1,4-diene-3,20-dione                                         17,21-dipropionate                                                                               17,21-dipropionate                                      20   6α-Fluoro-9α-bromo-                                                                  9β,11β-Epoxy-6α-fluoro-                      11β,17α,21-trihydroxy-                                                                17α,21-dihydroxy-                                      pregna-1,4-diene-3,20-dione                                                                      pregna-1,4-diene-3,20-dione                                  17,21-diacetate   17,21-diacetate                                         ______________________________________                                    

                  TABLE 1                                                          ______________________________________                                         Guanidine Bases                                                                R.sub.g                                                                               R.sub.1   R.sub.2   R.sub.3                                                                               R.sub.4                                                                               Score                                 ______________________________________                                         hydrogen                                                                              hydrogen  hydrogen  hydrogen                                                                              hydrogen                                                                              ++++                                  hydrogen                                                                              methyl    methyl    methyl methyl ++++                                  p-tolyl                                                                               morpholine      hydrogen p-tolyl                                                                               +++                                     i-propyl                                                                              phenyl    phenyl    hydrogen                                                                              i-propyl                                                                              +++                                   p-tolyl                                                                               pyrrolidine     hydrogen p-toly ++                                      i-propyl                                                                              cyclohexyl                                                                               cyclohexyl                                                                               hydrogen                                                                              i-propyl                                                                              ++                                    i-propyl                                                                              pyrrolidine     hydrogen i-propyl                                                                              +                                       cyclo- methyl    methyl    hydrogen                                                                              cyclo- +                                     hexyl                             hexyl                                        ______________________________________                                    

                  TABLE 2                                                          ______________________________________                                         Amidine Bases                                                                  R.sub.9   R.sub.3       R.sub.4 Score                                          ______________________________________                                         t-butyl   methyl        methyl  ++                                             n-butyl   methyl        methyl  +                                              cyclohexyl                                                                               methyl        methyl  +                                              phenyl    methyl        methyl  -                                              ______________________________________                                          ##STR1## 

I claim:
 1. A process for the preparation of an epoxide of the formulawhich comprises (1) contacting a 9α-substituted 11β-hydroxy steroid of the formula ##STR2## with an acyclic amine selected from the group consisting of compounds of the formula ##STR3## and (2) isolating the epoxide (II) where R_(a) is alkyl of one through 7 carbon atoms, cycloalkyl of 5 through 7 carbon atoms, phenyl substituted with one through 3--R, --OR₅₀ or --N(T₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine; R_(g) is R_(a) and a hydrogen atom, or phenyl; R₁ is alkyl of one through 7 carbon atoms, cycloalkyl of 5 through 7 carbon atoms, phenyl substituted with zero through 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine with the proviso that R₁ and R₂ combined cannot have more than 14 carbon atoms; R₁ and R₂ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine; R₂ is alkyl of one through 7 carbon atoms, cycloalkyl of 5 through 7 carbon atoms, phenyl substituted with zero through 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine with the proviso that R₁ and R₂ combined cannot have more than 14 carbon atoms; R₁ and R₂ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine; R₃ is alkyl of one through 7 carbon atoms, cycloalkyl of 5 through 7 carbon atoms, phenyl substituted with zero through 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine with the proviso that R₃ and R₄ combined cannot have more than 14 carbon atoms; R₃ and R₄ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine; R₃ ' is alkyl of one through 7 carbon atoms, cycloalkyl of 5 through 7 carbon atoms, phenyl substituted with one through 3--R, --OR₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a secondary amine selected from the group consisting of piperidine, pyrrolidine or morpholine, with the proviso that R₃ ' and R₄ ' combined cannot have more than 14 carbon atoms; R₃ ' and R₄ ' combined cannot have more than 14 carbon atoms; R₃ ' and R₄ ' can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine; R₄ is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with zero thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine with the proviso that R₃ and R₄ combined cannot have more than 14 carbon atoms; R₃ and R₄ can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine; R₄ ' is alkyl of one thru 7 carbon atoms, cycloalkyl of 5 thru 7 carbon atoms, phenyl substituted with one thru 3--R, --OR₅₀ or --N(R₅₀)₂ where with the amine the R₅₀ 's can be the same or different and can be combined to form a secondary amine selected from the group consisting of piperidine, pyrrolidine or morpholine, with the proviso that R₃ ' and R₄ ' combined cannot have more than 14 carbon atoms; R₃ ' and R₄ ' can be combined to form a cyclic secondary amine selected from the group consisting of piperidine, pyrrolidine and morpholine; R₆ is a hydrogen or fluorine atom or methyl group; R₉ is a chlorine, bromine or iodine atom or hydroxyl group as the tosylate, mesylate, or triflate ester; R₁₆ is a hydrogen atom, hydroxyl, acyloxy where the acyl group contains 2 thru 6 carbon atoms, or methyl group with the proviso that when R₁₆ is a hydroxyl group and when R₁₇ is a hydrogen atom the hydroxyl groups at C₁₆ and C₁₇ can be in the form of an acetonide; R₁₇ is a hydrogen atom or a --COR₁₇ α group with the proviso that when R₁₇ is a hydrogen atom and R₁₆ is a hydroxyl group the hydroxyl groups at C₁₆ and C₁₇ can be in the form of an acetonide; R₁₇ α is an alkyl of one thru 6 carbon atoms or phenyl; R₂₁ is alkyl of one thru 6 carbon atoms or phenyl, or phenyl substituted with p-nitro or m-methoxy groups; R₅₀ is a hydrogen atom or alkyl of 1 thru 3 carbon atoms; ˜ indicates the attached atom or group can be in the alpha or beta configuration; and is a single or double bond.
 2. A process according to claim 1 where the 9α-substituted-11β-hydroxy steroid (I) is selected from the group consisting of Δ⁴ -3-keto steroids ##STR4## Δ¹. 4 -3-keto steroids ##STR5## or 3β-hydroxy steroids ##STR6##
 3. A process according to claim 1 where the acyclic amine is an amidine of the formula ##STR7##
 4. A process according to claim 3 where R_(a) is t-butyl.
 5. A process according to claim 3 where R'₃ and R'₄ are both methyl groups.
 6. A process according to claim 1 where the acyclic amine is a guanidine of the formula. ##STR8##
 7. A process according to claim 6 where R_(g) is a hydrogen atom.
 8. A process according to claim 6 where R₁, R₂, R₃ and R₄ are all hydrogen atoms or methyl groups.
 9. A process according to claim 1 where the reaction is performed in the temperature range of about 0° to about 100°.
 10. A process according to claim 1 where about two equivalents of the acyclic amine per equivalent of steroid are used.
 11. A process according to claim 1 where R₉ is a bromine atom.
 12. A process according to claim 1 where the steroid D ring is ##STR9## where R₁₆, R₁₇, R₂₁ and ˜ are defined in claim
 1. 13. A process according to claim 1 where the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxypregna-1,4-diene-3,20-dione 21-acetate.
 14. A process according to claim 1 where the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxyprena-4-ene-3,20-dione 21-acetate.
 15. A process according to claim 1 where the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione 21-benzoate.
 16. A process according to claim 1 where the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxy-16α-methylpregna-1,4-diene-3,20-dione 21-acetate.
 17. A process according to claim 1 where the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-6α-fluoro-11β,16α,17α,21-tetrahydroxypregna-1,4-diene-3,20-dione 16,17-acetonide-21-acetate.
 18. A process according to claim 1 where the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,16α,17α,21-tetrahydroxypregn-4-ene-3,20-dione 16,21-diacetate.
 19. A process according to claim 1 where the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,16α,17α,21-tetrahydroxypregna-1,4-diene-3,20-dione 16,21-diacetate.
 20. A process according to claim 6 where the acyclic amine base (III) is tetramethylguanidine.
 21. A process according to claim 6 where the acyclic amine base (III) is guanidine.
 22. A process according to claim 3 where the acyclic amine base (IV) is t-butyldimethylamidine.
 23. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,16α,17α,21-tetrahydroxypregn-4-en-3,20-dione 21-acetate.
 24. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 6α-fluoro-9α-bromo-11β,16α,17α,21-tetrahydroxypregn-4-en-3,20-dione 21-acetate.
 25. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,16α,17α,21-tetrahydroxypregna-1,4-diene-3,20-dione 21-acetate.
 26. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 6α-fluoro-9α-bromo-11β,16α,17α,21-tetrahydroxypregna-1,4-diene-3,20-dione 21-acetate.
 27. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione 17,21-diacetate.
 28. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione 17-benzoate.
 29. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione 21-pivalate.
 30. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione 21-valerate.
 31. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione 21-propionate.
 32. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 9α-bromo-11β,17α,21-trihydroxy-16β-methylpregna-1,4-diene-3,20-dione 17,21-dipropionate.
 33. A process according to claim 1 wherein the 9α-substituted-11β-hydroxy steroid (I) is 6α-fluoro-9α-bromo-11β,17α,21-trihydroxypregna-1,4-diene-3,20-dione 17,21-diacetate. 